Raja, i'm wondering when the film you saw dates from. It seems to me that the trance state achieved by the keris dancers is similar to the trances of intitiates in Vodoun ceremonies in Haiti. For the most part, these rituals, at least the ones in public spaces, are theatre pieces performed to entertain the tourists (though, unfortunately, there is not much tourism in Haiti these days). This, of course, was not always the case as these dances once held profound cultural significance for the Balinese people. I have never seen film of the keris dance, but there are some very interesting photographs taken back in 1949 by famed photojournalist Henri Catier Bresson. I believe his wife at the time was Balinese herself. It is difficult to tell with still photograph, but the keris used then do not appear to have much flex to them. All the blades appear straight and rigged and are being pushed with considerable force against the skin of the dancers. There is not enough detail to tell, but where i can see the hilts they appear to be of the Bali type. As for the blades, it is hard to tell. They are not of the extra long (17in. or more) Bali type, but neither are they short. To stab one's self requires the blade to be a bit less than arms length. Anyway, my point really is, i guess, that things ain't what they used to be. I don't think very springy blades were always used for this ceremony and the power of trance states and belief is not to be under estimated. Still, i would like to see the film you mentioned. Is it available anywhere?